Water injection derichment device



s. s. Fox

WATER INJECTION DERIcmcEN'r DEVICE Filed April 1s, 1944.

INVENTOR Sept. 5, l 950 Saure? S. Fox BY M lm Patented Sept. 5, 19502,521,002 WATER INJECTIQN DERICBMENI DEVICE Samuel S. Fox, WestHartford, Conn., aasignor to United Aircraft Corporation, East Hartford,Conn., a corporation of Delaware Application April 13, 1944, Serial No.530,935

Claims.

This invention relates to improvements in apparatus for operating aninternal combustion engine with a charge including a combustionmodifying ingredient, such as water or a mixture of water and alcohol.

An object of this invention is to provide an improvement or modificationin a charge mixture strength controlling means, which is particularlyadapted for use with the ingredient injection apparatus disclosed andclaimed in the application of Robert C. Palmer, Jr., Serial No. 529,104,filed April 1, 1944, and assigned to applicants assignee.

Other objects and advantages will be apparent from the specification andclaims, and from the accompanying drawing which illustrates what is nowconsidered to be a preferred embodiment of the invention.

The single figure of drawing shows a diagrammatic view, partly insection, of a water injection apparatus, including the mixture controlmeans of this invention.

According to this invention, a pressure type carburetor is provided withtwo separate jets, in place of the co-nventional economized jet,arranged in parallel. One of these jets, which may be called aderichment jet, is controlled by a valve subjected to the inlet waterpressure of a. water injection regulator, and is arranged to beautomatically closed when water is being fed to the engine charge.

Referring to the drawing, supercharger |2 pumps air from manifold 22 toan annular co1- lector chamber |3, from which the charging fluid may befed to an engine, such as a. radial aircooled aircraft engine, by way ofoutlets I5 in a known manner. Manifold 22 may be open to the atmosphere,or it may be connected with the outlet of an auxiliary superchargerstage as disclosed in the Palmer application, identified above, and towhich reference is made for a detailed description of a chargingapparatus with which this invention is particularly adapted for use.

The mass or weight rate of airflow to the engine may be controlled by amanually operated throttle 24, to vary the power output of the engine.This varying airflow is continuously measured by the carburetorVenturi/section 30, which maintains an air pressure differential acrossthe diaphragm 28 of tlgfcarburetor air metering section 26 which isafuncticn of the rate of flow by weight of mtek'faar. Air diaphragm 2sacts in conjunction with fuel diaphragm 64, which is subjected to thefuel metering pressure differential, to actuate the fuel valve 52 so asto control the rate of flow of fuel through line 41 from the fuel tank42 to the fuel feed line 68 leading to the engine in proportion to therate of flow by weight of intake air. Unmetered fuel, at a pressureregulated by the valve 52, passes to the fuel control body 58 through aconduit 56 and after being metered by the various jets 66, 10, 12, 16and economizer valve 80 of the fuel control body, is passed to thedischargenozzle |42 through feed line 08 and injected into the spinnercup |54, from which it is centrifugally thrown into the airstreampassing through the supercharger, as disclosed and claimed in the patentto Buck, No. 2,287,021, granted June 23, 1942, and assigned toapplicants assignee. A metered fuel pressure transfer line 60 connectsfuel pressure regulator 44 with the metered fuel in fuel control body56.

Water from tank |04 may also be supplied to the engine charge, beingforced by pump |00 through line ||2, regulator |06, and feed line |30 tothe common feed line |40 in which it is mixed with fuel flowing to theengine through the fuel feed line 68. For proportioning the flow ofwater to the flow of intake air, valve |22 in water regulator |06 isactuated by diaphragm |26 subjected on one side to unmetered fuelpressure admitted to chamber |24 through line |28 and on the other sideto the pressure of the water admitted to chamber |30 by valve |22. Thisdiaphragm controls valve |22 so as to maintain the water pressure inchamber |30 (which is the unmetered water pressure ahead of water jet|34) equal to the unmetered fuel pressure in chamber |24. The waterpressure on the downstream side of the water metering jet |34 will beequal to the metered fuel pressure on the downstream side of the fuelmetering jets in the fuel control body 58, because the fuel feed line618 and the water feed line |36 are interconnected and discharge into acommon line |40.y As diaphragm |26 actuates valve |22 so as to maintainthe unmetered water pressure equal to the unmetered fuel pressure, itwill be seen that the regulator |06 maintains the water pressure dropacross the water jet |34 equal to the fuel pressure drop across the fuelmetering Jets. 'Ihe fuel metering pressure differential is controlled asa function of the rate of ow of intake air by air section 26 and fuelsection 44, hence the water metering pressure differential will also bea function of the rate of flow of intake air and consequently thequantity of water supplied to the engine will be proportioned to thequantity of air supplied to the engine.

Solenoid valve |02 is provided for admitting water to the engine at thewill of'the operator. When this valve is opened, :water under pressureopen check valve ||0, and flow to inlet water chamber |20, from which itwill be admitted to the engine in predetermined proportion to the flowof intake air by valve |22 and water jet |34. Supply line ||2 is ventedto tank |04 by a vent 4.

Regulator |06 is connected to fuel control body 50 by a water pressuretransfer line |60 which connects inlet chamber of the regulator withchamber |50 on one side of diaphragm |52 actuating derichment valve 82,which controls the :dow through fuel passage l62leading to derichmentjet 12. Chamber |54 on the other side of diaphragm |52 is subjected tounmetered fuel pressure by passage |53, connected withthe inlet chamber|56 of the fuel control body. A spring |58V biases valve 02 in anopening direction.

When valve |02 is closed and water is not being added to the enginecharge, the pressure in chambers and |20 of regulator |06 will be equalto the pressure in water /feed line |36 and hence will be equal to themetered fuel pressure in fuel feed line 68. No 'water will be flowing tothe engine, because valve |02 is closed, and hence there will be nopressure drop across water jet |34. Under these conditions the pressurein chamber |50 of the derichment valve on the fuel control body willalso be equal to metered fuel pressure, which is less than the unmeteredfuel pressure in chamber |54. The fluid pressure forces acting ondiaphragm' |52 will tend to move this diaphragm downwardly, in a valveopening direction. This action is'aided by compression sping |58. Thus,when 'water is not being injected, economizer jet 10 and derichment jet12 will both be open and will act together-to limit the maximum amountof supplementary fuel added to the intake air by fthe action of theauto-rich jet 16 (which is controlled by a manual valve 11) and theeconomizer valve 80 (which is automaticallycontrolled by diaphragm 84),just as does the singltgeconomizer jet of a conventional fuel controlbody. Economizer valve diaphragm 84 is subjected to the fuel meteringpressure differential by passage 85 and transfer line 06.

When valve |02 is opened and water starts to flow to the engine, thepressure in inlet chamber `|20 will 'immediately buildup to :a valuewhich 'is 'approximately the same -`as the loperating ,pressure createdby pump l|||0 in line ||2, and which is greater than the pressure lthatwill hema-in- 'tained lfin 'the unmetered water chamber '|30 by valve|22. Pumps |00:and 46 are of a known type. providing a substantiallyconstant ldischarge pressure `above lthe reference Vpressure in-balancingline v| l0, .connected to manifo`1d22. TheLpres- Sure inderichment chamber |50 is held equal t0 'thepressure in chamber |20 byline |60 and this pressure is suillciently great, when water -is flowingto the engine, to overcome the force `exerted downwardly on diaphragm@|52 Eby the unme'tered 'fuel pressure in chamber |54 and vthe spring|50, `and valve 82 will be closed to shut off the now of vfuel throughderichment jet 12. Just .as soon as the .flow of 'water lis lstarted tothe engine, "theflow ofsupplementary fuel, which was previously limited4by both jets '10 and 12, will '.be limited to a lower maximum lasdetermined by 'the ow capacity of jet '110 only, because jet 12 will'becut out by 'the closing of valve 62. When -water is 'through theregulator |06, valve '82 Awill strength of the engine charge will beautomatically decreased to a value providing the desired engineoperating characteristics for a charge including the combustionmodifying ingredient. In other words, fuel control body 58 and the waterregulator |06 cooperate to provide a predetermined lower maximum mixturestrength or maximum fuel air-ratio when water is being supplied to theengine charge. The engine may be supplied with different charges atdifferent times, with the ingredients of each charge being alwaysproportioned in predetermined ratio to each other, said predeterminedratio being automatically altered or adjusted to provide the mostdesirable charge proportions according to the nature of the ingredientscomposing the charge.

Valve 82 will be held open by the pressure of the fuel in chamber |54and the force of spring |58 except when operating water pressure ismaintained in chamber |20 of the water regulator. A failure or an unduedrop in the operating pressure in chamber.|20 for any reason, forinstance as might be caused by exhaustion of the water in tank |04, willenable valve 82 to open and prevent damage that might otherwise resultfrom operating the engine at the lower mixture strengths, without water.The structure is simple, reliable, and eflicient and acts immediatelyand positively to reset the mixture control to a best power or otherdesired fuel-air ratio when the flow of charging water, or otheringredient, is started; the change in fuel-air ratio being determined bythe characteristics of derichment jet 12, independently of the quantityof water flow.

It is to be understood that the invention is not limited to the specificembodiment herein illustrated and described, but may be used in otherways without departure from its spirit as deflned by the followingclaims.

I claim:

l. In a water injection Yapparatus `for an :internal combustion engine,,means for charging an engine with a mixture of fuel and air, a devicefor varying the fuel-air ratio of the `engine charge, a pump forlsupplying water under `pressure to the engine charge, a valve vforregulating .the ow of said water in accordance with the flow of chargingair, and .means Lsubjected vto the pressure of the water between ysaid-pump and said valve .for adjusting said device to vary said fuel-airratio.

i2. In la water injection apparatus, la vwater regulator :including yawater valve and an inlet water 'passage' for said valve, .a yfuelcontrol body including va fuel .meteringjet fand means responsive vto4an .increase in "the pressure of the water lin said inlet .passage.forfstopping the flow of fuel 'through said jet. 4

3. In van internal combustion engine. means for feeding charging fairvto saidengine, means for feeding fuel to said engine in predeterminedratio to thequantityoif charging rair, means for feeding Aa-coxnbustionmodifying liquid ingredient to said engine in predetermined ratio to thequantity of charging air, and means unaffected by normal Yvariations inthe rate of` flow of said ingredient `through an operating range ofingredient fiows Y for changing said fuel-air ratio upon a substan foran-internal combustion engine having an air intake, a fuel supplv line,.means including a fuel be held l,closed and the maximum 4mixture ,70`flOWregulating valve in said fuel line for regulating the flow of fuelto said engine in accordance with the flow of engine intake air, aningredient supply line, means including an ingredient flow regulatingvalve in said ingredient line for regulating the ilow of ingredient tosaid 'engine in accordance with the flow of engine intake air, aningredient control valve in said inulating the flow of fuel to saidengine, mechanism operatively associated with said fuel flow regulatingmechanism for regulating the flow of water to said engine, and a fuelpressure and water pressure responsive device operatively associatedwith said fuel flow regulating mechanism and with said water flowregulating mechanism for instantaneously shifting the fuel-air ratio ofsaid engine a predetermined amount when the flow of water to said enginethrough said water flow regulating mechanism ceases.

6. In a water injection apparatus for an engine, a fuel control meansincluding a fuel metering jet and a valve for controlling thc flow offuel through said jet, and means responsive to fuel pressure and towater pressure for actuating said valve.

7. In a water injection apparatus for an engine having a main fuelmetering jet and an auxiliary metering jet of fixed flow capacity, avalve separate from said auxiliary jet for starting and stopping theflow of fuel through said auxiliary Jet to the engine, and means foroperating said valve in response to initiation of water flow to theengine.

8. A fuel control body comprising, a main fuel metering jet, a fueleconomizer jet, an additional fuel jet, an economizer valve in serieswith each of said second and third named jets for regulating the flow offuel according to intake airflow, a valve for controlling the flow offuel through said additional fuel jet and means for actuating said lastnamed valve responsive to the pressure of the fuel on one side of themain fuel jet and also responsive to the pressure of a combustionmodifying ingredient.

9. A fuel control body comprising, a main fuel metering jet, a fueleconomizer jet, an additional fuel jet, a valve for controlling the flowof fuel through an additional jet, means for introducing a fluidcomprising water and another combustion modifying ingredient into saidfuel, and pressure responsive means for actuating said valve by saidfuel and said fluid.

10. In an apparatus for introducing a liquid ingredient into a mixingchamber, an air conduit having a mixing chamber, means for feeding fuelto said chamber, means for feeding ingredient to said chamber, a `valvehaving opened and closed positions for starting and stopping the flow ofa predetermined portion of said fuel flow to said chamber, when thevalve is in the closed position the remainder of the fuel flow continueson to said chamber, means for passing the remainder of the fuel on tosaid chamber, a second valve having opened and closed positions forstarting and stopping the now of vingredient to said chamber, and meansfor instantaneously closing said first valve when the said second valveis opened and for instantaneously opening said first valve when thesecond second valve is closed.

SAMUEL S. FOX.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,029,740 Beck June 18, 19122,076,606 Winter Apr. 13, 1937 2,150,764 Farineau Mar. 14, 19392,236,032 Helgeson Mar. 25, 1941 2,311,827 Hansen Feb. 23, 19432,348,008 Hunt May 2, 1944 2,361,227 Mock Oct. 24, 1944 2,392,565Anderson et al Jan. 8, 1946 2,447,264 Beardsley Aug. 17, 1948 FOREIGNPATENTS Number Country Date 826,695 France Apr. 6, 1938 828,458 FranceMay 18, 1938 Certicate of Correction Patent No. 2,521,002 September 5,1950 SAMUEL S. FOX

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows:

Column 6, line 8, for the Word an before additional read said; line 29,for second second read said second;

and that the said Letters Patent should be read as corrected above, sothat the same may conform to the record of the case in the Patent OHice.

Signed and sealed this 28th day of November, A. D. 1950.

THOMAS F. MURPHY,

Assistant Gommz'ssz'oner of Patents.

